A huge batch of fake US Treasury bonds worth some $6 trillion – more than a third of the US national debt – has been seized by Italian police. Eight Italians have been arrested and accused of a large-scale international fraud.

­The fake bonds and other securities were seized from a Swiss trust company during a joint operation by Italian, Swiss, and US authorities. The fake certificates signed "Chicago, Illinois, Federal Reserve Bank" were stored in trunks stamped with “Federal Reserve System, Treaty of Versailles” marks. The bonds were carrying the false date of issue of 1934.

The forgers were planning to use the fake certificates as collateral to secure loans in a number of Swiss banks, prosecutor of the southern Italian city of Potenza said as cited by Reuters.

The investigation began over a year ago as a trivial probe into Italian mafia loan-sharking. However, after the Italian authorities uncovered an international network plotting a full-scale fraud, they called upon their Swiss and US colleagues. The US experts helped to identify the bonds as fakes.

This is not the first attempt to defraud Swiss banks with fake US bonds, but the most ambitious so far.

In 2009 the officers of the Italian financial police arrested two Japanese nationals who tried to cross the Italian border and enter Switzerland with a suitcase full of fake US treasury bonds worth $134.5 billion.

In a similar incident in 2009 two Filipinos were arrested at Milan Airport with a bag of fake US bonds amounting to some $180 billion.

In January last year six smugglers were arrested during a routine search at a highway rest shop. They were carrying a briefcase full of fake bonds valued at approximately $20 billion.